As shown in FIGS. 10 to 11, a first embodiment of a conventional constant electric power-supplying device 50 is disclosed in Japanese patent application No. JP-A, 2001-354085 (pages 7 to 9 and 11, FIGS. 4, 7, 13).
This supplying device 50 is arranged in a sliding door 41 of a vehicle, and includes a protector 42 made of synthetic resin for bendably receiving a wiring harness 43 (a cover of the protector 42 is omitted in FIGS. 10, 11), and a metallic flat spring 44 for pushing upward the wiring harness 43 in the protector 42.
A lower end of the flat spring 44 and the wiring harness 43 are fixed to the protector 42 at a lower front thereof. A front side of the flat spring 44 supports the wiring harness 43 slidably. A spring cap 49 made of synthetic resin is mounted on the flat spring 44 at a front end thereof. The spring cap 49 firmly supports the wiring harness 43.
The wiring harness 43 is composed of a plurality of electric wires 43a covered by a corrugate tube 43b made of synthetic resin. A lower front part of the corrugate tube 43b is fixed to the protector 42 by such as a rolling tape. The corrugate tube 43b is easy to be bent by having grooves and projected lines arranged alternately.
The wires 43a at one end of the wiring harness 43 is led out from a front end of the protector 42 and connected to an auxiliary at the sliding door side. The corrugate tube 43b of the wiring harness 43 is arranged swingably in a vehicle body 47 through an oblong bottom opening 45 of the protector 42 and a connecting space 46. In the connecting space 46, the corrugate tube 43b covers and protects the wire 43a from outer interference, water drops, dusts, and the like.
As shown in FIGS. 10 and 11, the wiring harness 43 is pulled backward in a fully closed sliding door 41 and pulled forward in the fully opened sliding door 41. In the half opened sliding door 41, the flat spring 44 pushes upward the wiring harness 43 to absorb the slack of the wiring harness 43. Therefore, the flat spring 44 prevents the wiring harness 43 from being caught in the sliding door 41 at the slack of the wiring harness 43.
As shown in FIG. 12, a second embodiment of a conventional electric power-supplying device 50′ has a flection-regulating wall 71 mounted on a protector base. This flection-regulating wall 71 is in a half looped shape and prevents the wiring harness 43′ and the flat spring 44′ from being bent in a radius less than a radius of the flection-regulating wall 71.
When the sliding door 41 is pulled rapidly to be fully opened, the wiring harness 43′ is strongly pulled forward, however, the wiring harness 43′ and the flat spring 44′ abut on the flection-regulating wall 71 and the further bends thereof are prevented. Therefore, damage of the wiring harness 43′, degradation of the flat spring 44′ and the like are prevented.
However, in the conventional electric power-supplying device 50′, for example, when the flat spring 44′ becomes longer corresponding to an increase of the slack of the wiring harness 43′, and a spring cap 49′ made of synthetic resin and attached to a front end of the flat spring 44′ contacts slidingly with the flection-regulating wall 71, there is a problem that excessive repetition of the slides may abrade the flection-regulating wall 71 and the spring cap 49′ or frictional resistance between the flection-regulating wall 71′ and the spring cap 49′ may increase. Thereby, it may be difficult to lead out the wiring harness 43′ for absorbing the slack thereof. Further, there is another problem that an increase of the slack to be absorbed enlarges the protector 42′ in a height direction and restricts layout design flexibility of components to be mounted on the sliding door 41.
Accordingly, an object of the present invention is to provide a continuous electric power-supplying device to decrease frictional resistance between the spring cap as a harness retaining member attached to the flat spring and the flection-regulating wall for easily leading out the wiring harness, easily absorbing the slack of the wiring harness and allowing the protector to have a lower height.